It's a well-known fact that the King of Rock n' Roll enjoyed practicing karate. What might not be so well-known is that he was pretty good at it, too. After starting his training while in the Army in Europe in 1958, Elvis Presley studied martial arts until his death in 1977 — when he was a seventh-degree black belt.

This talent came in handy one night when rocker Alice Cooper pulled a gun on him.

Elvis earned his black belt after a rigorous six-week-long training regimen and test. Though his fighting style wasn't "pretty," the King still passed the test. Elvis would even eventually start his own dojo, the Tennessee Karate Institute, and write books about how he trained for real-life dangers — including meditations on how to prepare for attackers with real guns.

Elvis (left) in a karate demonstration.(YouTube)

He was so serious about the art that he was ready to be promoted beyond the level of his trainer much faster than anyone could've anticipated. He was as bold in the studio as he was in real life: Presley once even got out of his limo at an intersection in Madison, Wisconsin, to stop a fight at a gas station. The then-42-year-old walked up to the fight, told the two men, "I'll take you two on," and assumed a karate stance. The two men stopped fighting.

"Is everything settled now?" he said.

Despite not being considered "pretty" when he first earned his black belt, Elvis' karate improved greatly over the next 15 years. Wayne Carman, who trained with Elvis under their master, Kang Rhee, said this about Presley's karate:

"His technique was crisp and powerful and his movements were graceful."

It was a good thing, too. One night in Las Vegas, Elvis was in the penthouse of a hotel when a young Alice Cooper (along with Liza Minelli and Linda Lovelace) came into his room. He wasn't just looking for an audience with the King. After they were all frisked by Elvis' security, Elvis took Cooper into the kitchen and took out a .32 snub-nose revolver. He told the kid to put it to his head.

Cooper recounted the story to the UK's Mirror:

"I had this gun in my hand and was expecting one of his security to come in any second, see me holding a weapon, and shoot me dead... A little voice in my left ear was telling me, 'Go on, this is history, kill him, you'll always be the guy who killed Elvis.' In my other ear was another voice saying, 'You can't kill him, it's Elvis Presley – wound him instead, you'll only get a few years!'.

You come at the King, you best not miss.

That's when Elvis did a flying kick at the gun, knocking it out of Cooper's hand. He then tripped Cooper and pinned him to the ground by his neck.